"Ross Herbert" wrote in message
...
On Fri, 23 Sep 2005 23:46:16 GMT, "Bob Kos"
wrote:
"Ross Herbert" wrote in message
.. .
On Wed, 21 Sep 2005 21:53:21 GMT, "Bob Kos"
wrote:
"Ross Herbert" wrote in message
.. .
It is difficult to be specific about where you might obtain a
replacement since there is no manufacturer info on the inductor
photo.
The physical size is also difficult to guess but I am thinking it
would be something like 8mm x 8mm and about 4mm high and it is
unshielded. The wire gauge doesn't appear to be that large so it is
most likely not a high current inductor (possibly around 1A). Also,
on
second thought, the value is more likely to be 27uH and not 270uH.
In looking at what is around on the www it would most likely be
similar to the Delevan 3483R-270M listed on this page
http://www.delevan.com/product/src/s...3483_S3483.pdf
If further info is available then I could probably be a bit more
helpful.
Hi:
I hunted around Mouser's site till I found the smallest 270 uh
inductor
that
I could find that looked similar to mine. Although it was close, it
was
still too large for the PCB inside the drive. I simply relocated it
to a
place where it's larger size could be accomodated and ran short jumper
wires
to connect it to the PCB pads. The drive is up and running just fine.
I
admit that I may have the wrong value for this part. But I'll use it
and
see how it holds up.
Thanks much to all who responded to my query. I couldn't have fixed
it
without your help.
Bob
Did you notice that I had revised my thinking on the inductance value?
It is more likely a 27uH than 270uH.
Hi Ross:
I did notice that you changed your suggestion on the value of the
inductor.
I had already ordered the 270 uh part and received it before I saw your
later post. I'm wondering what the ramifications of using the 270 uh vs
the
27 uh part? The part appears to be in a DC / DC converter. What are
your
thoughts on the substitution? If it will destroy the drive, I'll order
another per your post. Otherwise I'll leave it run & see if it reads /
writes reliably. It does do those things now.
It is not possible for me to say exactly what the inductance value is
without the original manufacturer's specs. I have seen some
manufacturers mark an inductor with 270 to signify 270uH but in other
cases a 270 marking will mean 27uH. Unless you can actually measure
the value of the original inductor then one can only guess.
Not having actually tried using an inductor 10x higher than the design
value I can't say exactly. If it is the output inductor of the
switcher I would guess that it might drastically affect the output
voltage at best. It may cause the IC to run hotter than intended and I
wouldn't want to try it if it meant I had to replace the IC
afterwards. Better to stick to the design value.
I have another identical inductor on this board. Is it feasible to
calculate the value of it while it is in circuit? If so, can you offer me
help on how to determine the value? Is it a resistance type of measurement?
I'm a bit out of my league in trying to determine how to measure this
inductor. Again, your help is greatly appreciated.